Pumping apparatus



Au. is, w46. H. s. COE

PUMPING APPARATUS lNVg-:NTOR Har/'won .i Coe www YI ATTORNEY Au., n, ma

PUMPING APPARATUS Filed Aug. 19, 1944 2 Sheets-Sheet 2 lNyENToR /arr/son5. Coe

ATTORNEY Patented Aug. 13, 1946 UNITED STATES PATENT OFFICE PUMPINGAPPARATUS Harrison S. Coe, Palo Alto, Calif.

Application August 19, 1944, Serial vNo. :550,240

(ci. s- 44) 14 Claims.

corrosion where abrasive or corrosive iluids arev being pumped.

To obtain eicient operation in a pinnp of this type, the .diaphragm mustpulsate freely, or without undue strain, in its expansion andcontraction .of the pumping compartment. Since, for like .positions ofthe piston in the cylinder, the degree of expansion or contraction 'ofthe pumping compartment depends entirely upon the volume of impellingliquid in the pump, it will be obvious that the free movement of the`diaphragm, throughout a stroke of the piston, can only be lmaintainedif the impelling liquid remains constant within narrow limits.

While this class of pump has marked advantages over ordinary pistonpumps where abrasive or corrosive liquids are to be handled and is usedunder some especially severe` conditions i-n the pumping of mud indrilling of oil wells and like services, its application, up to thepresent, has been very restricted, because of leakage of fluid past thepiston that actuates the impelling liquid. This leakage is nevercompletely avoidable and has kmade it necessary to stop the pump ai',intervals, dependent upon the rate of leakage, and adjust the volume ofimpelling liquid and displace any accumulated air in the impellingliquid compartment. Another factor tending to limit the application ofthe type of pump under consideration has been the deleterious effect onthe apparatus and its operation produced by the overheating of theimpelling liquid due to its friction in the pump.

Another factor which has heretofore presented difficulty in this type ofpump arises from the tendency of solids and air, separating from thematerial rbeing pumped, to accumulate in parts of the pumpingcompartment .and interfere with eicient operation.

It is an object of the present invention to provide means to maintainthe diaphragm in position to pulsate freely .and without strain.

It is a further object of the present invention to provide means toprevent air from accumulating in the impelling liquid compartment and toreplace liquid escaping therefrom.

It is a further object of the present invention to provide means tointroduce liquid into the impelling liquid compartmentl and to expelliquid therefrom and thereby .remove heat generated therein.

Other objects and advantages will appear from the followingspecification and drawings .in which:

Figure 1 is a side view, in cross-section, of a diaphragm'vpumpincorporating the preferred embodiment of my invention.

Figure 2 is a cross-sectional detail taken along the line 2-2 of Figure1.

Figure 3 is a cross-sectional'view taken along the line 3-'3 of Figurev1`.

Figure 4 is a modification of the invention illustrated in Figure 1 'inwhich a diierent type of diaphragm is used.

As shown in Figure 1 there is provided Va chamber lIU of oblong ovalform, which is provided with annular flanges l! and I2 at its upper andlower ends. Mounted above chamber I is a suitable outlet valve body I3which is secured thereto by suitable bolts 'through cooperating flangesI2 and Ill. An airtight and liquid-proof seal b'etween these members isobtained by the use of a' suitable gasket I 5. Mounted within valve bodyrI3 I have provided a poppet type valve I6 adapted to movelongitudinally and to Vbe operated by differential pressure thereon.Valve I6 is normally maintained in the position shown in vFigure 1 b-ygravity. When the pressure in body I3 below valve I6 suflicientlyexceeds the pressure in the larea above the valve, the same is opened.When .the pressure in body vI3 below valve I6 is less vthan the pressurein the area above the valve, the same maintains the position shown inFigure 1. vValvelbody I3 extends downwardly into chamber I0 forming acylindrical projection Il,

the use of which will hereafter .be explained.

Secured to the lower end of chamber Il@ and projecting inwardly theretoI have provided a cylindrical member I8 provided with orifice I9.

pressures within body 26.

Also secured to the lower end of chamber IU by suitable bolts andgaskets, is a valve body 20 and its cooperating poppet valve 2I of thesame type as vvalve I6 and likewise operated .by differential suitablyconnected .to a source of material to be pumped as "by means of flange22.

Within chamber -I0 I have provided a -diaphragm .or tube 30 made .ofilexiblematerial such The entire device is 3 Y as natural or syntheticrubber, which is secured at its ends to members I1 and I8 respectivelyby any suitable means to provide a liquid-proof seal. As shown in Figure1, diaphragm 30 may be secured to members I1 and I8 by clamps 3|.Extending downwardly from member I1 within tube 3l), I have provided anannular guard tube 32 to prevent the collapse of tube 30 into valve bodyI3.

Chamber Ill is provided with a cylindrical outlet 4Il'which is incommunication with cylinder 4I. Within cylinder 4| there is areciprocating piston or plunger (not shown) adapted to reciprocatelongitudinally therein as indicated by the arrow. On that portion ofdiaphragm 30 opposite orice 40 I have provided a metal plate 42 which isadapted to act as a shield against the direct impact on diaphragm 3Dcf'liquid entering chamber I through orifice 40 during the pressurestroke of the piston and to prevent diaphragm from being drawn undulytoward or into orice during the suction stroke of the piston. Diaphragm30 is preferably iluted as shown in Figure 3 in order that the same maybe expanded and contracted with the minimum of stretching As willhereinafter more fully be explained the space within chamber l0 andoutside of diaphragm 30 is termed an impelling liquid compartment, andthe same is lled with liquid hereinafter called impelling liquid. Uponreciprocaton of the piston within cylinder 4I a portion of the impellingliquid is alternately drawn into and out of the cylinder 4I therebycreating alternate suction and pressure pulsations within chamber I0.Alternate suction and pressure within chamber I0 expands and contractsthe area within diaphragm 30, known vas the pumping or impelled liquidcompartment thereby increasing or decreasing the pressure and volumewithin the same. As will be obvious to those skilled in the art,compression of tubular diaphragm 30 causes the impelled liquid ,thereinto be forced through conduit I3'past'valve I8. Expansion of tubulardiaphragm 30 creates differential pressure within the same and drawsliquid into the same through valve 2|.

As has previously been pointed out, on suction strokes of the pistonwithin cylinder 4I a small amount of air may be drawn into the impellingliquid compartment and ultimately this air seeks the highest pointtherein. To provide an escape for this air I have provided an oriceconnected by suitable piping 46 to a resistance means 41 vconsisting ofcylinder 48 within which I have mounted a screw member 49.' Passage ofliquid through orifice 45 is retarded thereby. Ballcheck valve 50 withinliquid holding chamber 5I prevents the sucking of liquid into theimpelling liquid compartment on the suction stroke. A suitable valve 52is provided in the event it is found desirable to adjust or close theescape system. As will be pointed out hereinafter, at times it may bedesirable to vent a portion of the impeiling liquid from chamber I0, andin that event baie41 and check valve 50 would operate in the same manneras with the escape 0f air. I contemplate that liquid chamber 5I may attimes function as a heat exchange unit to supply cool liquid to theimpelling liquid compartment.

To permit the introduction of liquid into the impelling liquidcompartment surrounding diaphragm 30, I have provided a novel valvemeans designated generally at 60. Valvermeans 6I! consiste generally ofa cylindrical housing or intermediate compartment BI which is incommunication with the impelling liquidcompartment by means of circularorifice or passage 62. Valve means 60 is suitably secured to chamber IIIto insure a liquid and air-proof seal therewith. Coaxially mountedwithin housing 6I I have provided a cylindrical member 63. Extendinginto the impelling liquid compartment through orifice 62 I have provideda push rod 64 adapted to operate valve member 65, which cooperates withvalve seat 66. Valve 65 is mounted adjacent one side of a piston 61which is slidably mounted within cylindrical member 63. Valve 65 isAadapted to close against seat E6, and when in engagement therewithprevents communication between housing 6I and chamber I. In order tomaintain push rod 64 accurately aligned within orifice 62 to preventjamming of the same, I have provided an axially aligneddnember 1I)adapted to cooperate with a cylindrical extension 1| upon piston 51.Spring 12 is adapted to urge piston 61 and valve 65 into closedposition, that is, against valve seat 65. The interior of cylinder 63 isin communication with the space surrounding cylinder 63 by restrictedorifice l13 in piston 61 and by orices 14 and 15 in cylindrical member63. Orifices 14 are provided with closure members 16 of the pinched tubetype which permit expulsion of liquid 4from Within the cylinder 63through orifices 14 but do not permit return of liquid into saidcylinder through said orifices. Orifices 13 and 15 are simple openingspermitting inow and outflow therethrough. It is obvious therefore thatliquid may be expelled from within cylinder 63 much more rapidly` thanit may enter. Orices 68 are provided in cylindrical extension 1I topermit the entry of liquid therein and prevent creation of a vacuum.Housing 6I is also in communication with a source of liquid supply 5Ithrough passage 11 and check valve 18. Check valve 1S permits the fiowof liquid from chamber 5I into housing 6I through passage 11 butprevents the expulsion of liquid from housing 6I through passage 11 intoliquid chamber 5 I.

Operation of the device and method may vbriefly be described as follows:A quantity of `impelling liquid is placed in the pump sucient toestablish pumping operation. The pump is attached to a source ofmaterial to be pumped by suitable connection to ange 22 on valve body28. A quantity of impelling liquid is placed in liquid supply chamber5I, and valve A52 is opened. Reciprocation of the piston within cylinder4I as has previously been explained, draws a portion of the impellingliquid within the impelling liquid compartment into cylinder 4I causingexpansion of tubular diaphragm 30 creating a differential pressuretherein and drawing liquid into the pumping compartment through valve2I. A pressure stroke of the impelling uid contracts diaphragm 3i] andexpels liquid from the pumping compartment outwardly through valve I6.

Air entering the impelling liquid compartment would be trapped inchamber II! at its highest point and would cause the difcultiespreviously enumerated. Air would tend to be` expelled upon a pressurestroke through orifice 45 and resistance means 41 into liquid chamber5I. As a matter of fact, under some conditions, air and liquid or liquidwould be expelled through orifice 46 to liquid chamber 5I. The flowthrough orice 45 may be controlled by resistance 41 and valve 52 asdesired.

In the event liquid within the impelling liquid compartment escapeslthrough orifice 45 or around the piston within cylinder 4I', it isobvious-thattubular `diaphragm 36 will expand and will strike push rod6d and urge valve 65 Vaway from its seat 66, thereby permittingcommunication between housing El and chamber l0, through orice 62. Whenvalve E5 is forced away from its seat yESS, piston 61 is moved intocylinder .63, forcing liquid outwardly therefrom through oriiices 13 andM. When, upon the following pressure stroke, tubular diaphragm 3Q iscontracted, it is no -longer in contact with push rod 64, and spring 'l2urges valve E5 toward closed position. Valve `65 is prevented fromclosing rapidly by virtue vof the fact that the sole route by whichliquid can reenter cylinder 63 is through metering orifice 'F3 in pistonSi' and oriiices 15. Oriices 'l5 will be closed by piston Sl until valve65 isfnearly closed. When piston S'Iwopens orifices 15, they will permita substantial increase in the flow of liquid into cylinder t3 and allowspring 12 to accelerate the closure of valve S5. However, flow of liquidrcm'the impelling liquid compartment into housing 6l through orifice 62upon the pressure stroke is prevented by check valve T8. Therefore upona pressure stroke no liquid or pressure in chamber iii is lost by virtueof the opening of valve 65. However upon the start of the followingsuctionstroke, liquid is drawn from liquid chamber 5| through conduit'Il into housing 6i and from there, through orice A62, into theimpelling within-chamber l0.

If liquid drawn in during the period when valve 65 is open balances theliquid being lost from the impelling liquid compartment, the operationis in equilibrium and the position of the di.. aphragm at the end of thesucceeding suction stroke remains Stabilized. If Valve closes tooquickly to admit liquid to balance this loss the diaphragm 3i] expandsand increases the range of movement of piston 67 thereby causing theperiod during which valve remains open to be extended and in turncausing more liquid to be drawn in through valve 18. This progressiveexpansion of diaphragm 30 will cease when the liquid drawn in balancesthe liquid loss. In rare cases liquid may enter through valve I8 duringthe period when valve 61 is open as diaphragm 30 approaches the end ofthe suction stroke. Under most conditions pressure exists in theimpelling liquid compartment during this period and all passage ofliquid through orice 52 will occur following the succeeding pressurestroke.

In the modication of my invention illustrated in Figure 4, the tubulardiaphragm 39 of Figure 1 is replaced Iby a simple exible sheet-likediaphragm 8l. Impelling liquid compartment 82 is suitably connected to areciprocating piston arrangement, not shown, by conduit 83. Operation ofthe impelling liquid within compartment 82 operates diaphragm 8l in muchthe same manner as the operation of diaphragm St as has heretofore beenexplained. Pulsation of diaphragm 8l creates alternate pressure andsuction within impelled liquid or pumping compartment 84 thereby causingthe entry of material through poppet valve 85 upon a suction stroke andexpulsion of material through poppet valve 86 upon a pressure stroke.Escape .of air or liquid through orifice 6l and into liquid chamber 88is identical to the escape of the same through oriiice 45 as pointed out.in connection with Figure l.

However the device permitting the introduction of compensating liquid tothe impelling liquid 'in compartment 82 from liquid chamber liquidcompartment n 6 88 is slightly different in the modification shown inFigure .2i than as shown in Figure 1. Upward movement of diaphragm t1upon a suction stroke causes diaphragm 8l to strike push rod 90 andraise valve 9| from itsseat 92 thereby permitting communication betweenimpelling iluid compartment 82 and valve chamber 93. Y Upward movementof valve 9! causes expulsion ci liquid above double piston arrangement94 through the rubber nipples `95 as previously explained in connectionwith the operation of valve means '60.

in Figure 1. However the return of valve SI to its closed positionissolely by gravity.l Reintroduction of liquid into the area above thedual valve 9i is permitted.

The cycle of operation and introduction of liquid into the impellingliquid compartment .is the same as has been previously explained inconnection with Figure l.

I claim:

l. In a pump having a chamber and a diaphragm within said chamber anddividing the same into an impelling liquid compartment and a pumpingcompartment, inlet and outlet valves permitting the inflow and outow ofliquid from said pumping compartment upon movement of` said diaphragm, aliquid holding chamber, valve means adapted to function in response tothe action of the diaphragm to allow 0r prevent communication betweensaid impelling liquid compartment and said liquid holding chamber, saidvalve means including means adapted to retard the closure of the valvethrough an interval of time dependent in duration on the volume ofliquid in the impelling liquid compartment.

2. In a diaphragm pump wherein the diaphragm is adapted t0 move inresponse to the action of impelling liquid in contact therewith, achamber adapted to act as a source of impelling liquid but spaced fromthe impelling liquid in contact with said diaphragm, a valve responsiveto the position of said diaphragm to permit or preventV communicationbetween said chamber and said impelling liquid in contact with saiddiaphragm, and means adapted to retard the closure of said valve throughan interval of time dependent upon the position of the diaphragm at theconclusion of its suction stroke. f

3. In a diaphragm pump wherein a diaphragm dividing an enclosed spaceinto a pumping compartment and an impelling liquid compartment isadapted to move in response to the action of impelling liquid in saidimpelling liquid compartment; a chamber adapted to act as a source ofYimpelling liquid and spaced from the impelling liquid compartment, valvemeans responsive to the position of said diaphragm and adapted to openand close a passage between said chamber and said impelling liquidcompartment, and means adapted to retard the closure of said passagethrough an interval of time dependent on the position of the diaphragmat the conclusion of its suction stroke.

4. 1n a diaphragm pump wherein a diaphragm dividing an `enclosed spaceinto a pumping com-- partment and an impelling liquid compartment ispelling liquid in said impelling liquid-compari',

ment; a chamber adapted to act as an intermediate source of impellingliquid, a passage leading from said chamber to an exterior sourceof-supply of impelling liquid, a valve adapted to close said passageunder the iniluence of pressure'in said chamber and to open said passageunder the influence of suction therein, a passage communicating saidchamber with said impelling liquid compartment, and means responsive tothe position of said diaphragm adapted to open and close said passage.

5. In a diaphragm pump wherein a diaphragm dividing an enclosed spaceinto a pumping compartment and an impelling liquid compartment isadapted to move in response to the action of impelling liquid in saidimpelling liquid compartment, a chamber adapted to act as anintermediate source of impelling liquid, a passage leading from saidchamber to an exterior source of supply of impelling liquid, a valveadapted to close said passage under the influence of pressure in saidchamber and to open it'under the influence of suction therein, a passagecommunicating said .chamber with said impelling liquid compartment,

valve means responsive to the position of said diaphragm and adapted toopen and close said passage, said valve means including a cylinderenclosed at one end, a piston in said cylinder, means adapted to cause amovement of said piston in said cylinder in response to an action of thediaphragm, means adapted to establish a force against said piston in theopposite direction to said movement, a valve adapted to maintain aposition in controlled relation to the position of said piston and toclose said passage between said chamber and said impelling liquidcompartment in response to movement of said piston under the influenceof said force, and means adapted to control the movement of the pistondue to said force including an orice adapted to admit liquid into saidcylinder.

6. In` a diaphragm pump wherein the diaphragm is adapted to move inresponse to the action of impelling liquid in contact therewith, achamber adapted to act as a source of impelling liquid and spaced fromthe impelling liquid in contact with said diaphragm, valve meansresponsive to the position of said diaphragm to permit communicationbetween said chamber and the impelling liquid in contact with saiddiaphragm, whereby the opening of said valve is controlled by themovement of said diaphragm and the closure of said valve is controlledby the metering of liquid into a uid chamber associated with said valvemeans.

7. In a pump, a compartment, a tubular diaphragm adapted to be mountedin said compartment and to divide the same into an inside pumpingcompartment and an outside impelling liquid compartment, an auxiliarysupply chamber, valve means adapted to permit or prevent the flow ofliquid from said auxiliary chamber to said impelling liquid compartmentand from said impelling liquid compartment tc 'said supply chamber, theopening of said valve means being controlled by the position of saiddiaphragm at the end of its suction stroke and closure of said valvemeans being controlled by metering of liquid into a fluid chamberassociated with said valve means.

8. In a diaphragm pump wherein a diaphragm dividing an enclosed spaceinto a pumping compartment and an impelling liquid Vcompartment isadapted to move in response to the action of the impelling liquid insaid impelling liquid compartment, a chamber adapted to act asintermediate source of impelling liquid, apassage leading from saidchamber to an exterior source of supply of impelling liquid, a valveadapted to close said passage under the influence of pressure in saidchamber and to open it under the influence of suction therein, a secondpassage communicating said chamber with said impelling liquidcompartment, valve means responsive to the position of said diaphragmandA adapted to open and close said second passage comprising acompartment of variable space, a member adapted to contract said spacein response to an action of the diaphragm, means adapted to exert aforce against said member tending to expand said space, a valveadapted'to maintain a controlled position in relation to the position ofsaid member and to open said passage on the contraction of said spaceand to close it on the expansion, of said space, and

means adapted to control the rate of expansion of said space.

9. A diaphragm pump embracing an enclosed space divided by a diaphragminto a pumping compartment and an impelling liquid compartment, anintermediate compartment separatingY the impelling Yliquid compartmentfrom a source of liquid supply, a passage leading from said source intosaid intermediate compartment, a valve in said passage adapted to admitliquid into and to close against the flow of liquid out of saidcompartment, a passage leading from said inter-l mediate compartmentinto said impelling liquid compartment, a valve adapted to open andclose said passage, means adapted to open said valve in response to anaction of the diaphragm, and means adapted to close said valve.

l0, A diaphragm pump embracing an enclosed space divided by a diaphragminto a pumping compartment and an impelling liquid compartment, anintermediate compartment separating the impelling liquid compartmentfrom a source of liquid supply, a passage leading from said source intosaid intermediate compartment, a valve in said passage adapted to admitliquid into and to close against the flow of liquid out of saidcompartment, a passage leading from said inter mediate compartment intosaid impelling liquid compartment, a valve adapted to open and closesaid passage, means adapted to open said valve in response to an actionof the diaphragm, means adapted to close said valve, and means adaptedto retard the closure of said valve, said means including a. chamber, apassage communicating said chamber with a body of liquid in the pump andmeans adapted to vary the volume of the space enclosed in said chamberin response to an action of the diaphragm. Y

Vll. A diaphragm pump embracing an enclosed space divided by a diaphragminto a pumping compartment and an impelling liquid compart-V ment, apassage leading from said impelling liquid compartment to a pointexterior to the pump andv adapted for the expulsion of fluid from thepump,v

passage adapted to admit liquid into and to closey against the flow ofliquid out of said compartment, a passage leading from said intermediatecompartment into said impelling liquid compartment, a valve adapted toopen and close said pas-f. sage, meansV adapted to open said valve inresponse,v

to an action of the diaphragm, and means adapted to close said valve.

12. A diaphragm pump embracing an enclosed space divided by a diaphragminto a pumping compartment and an impelling liquid compartment, apassage leading from said impelling liquid compartment to a pointexterior to the pump and adapted for the expulsion of fluid from thepump, an intermediate compartment separating the impelling liquidcompartment from a source of liquid supply, a passage leading from saidsource into said intermediate compartment, a valve in said passageadapted to admit liquid into and to close against the flow of liquid outof said compartment, a passage leading from said intermediatecompartment into said impelling liquid compartment, a valve adapted toopen and close said passage, means adapted to open said valve inresponse to an action of the diaphragm, means adapted to close saidvalve, and means adapted to retard the closure of said valve, said meansincluding a chamber, a passage .communicating said chamber With a bodyof liquid in the pump and means adapted to vary the volume of the spaceenclosed in said chamber in response to an action of the diaphragm.

13. In a pump characterized by a chamber and a diaphragm dividing saidchamber into an impelling liquid compartment and a pumping compartment,said diaphragm being adapted to pulsate in response to a reciprocatingmovement of liquid in said impelling liquid compartment and to causesuccessive periods of change in the volume of said pumping compartment;means adapted to admit liquid into said impelling liquid compartment,means adapted to function in response to an action of the diaphragm andto cause said rst named means to admit said liquid, and means adapted tocontrol the volume of liquid admitted by said first named means, saidmeans being adapted to function in accordance with the position occupiedby the diaphragm at the termination of a period of change in the volumeof the pumping compartment.

14. In a diaphragm pump incorporating a pumping chamber, an impellingliquidr chamber, and a diaphragm forming a dividing Wall between saidchambers, an intermediate chamber between the impelling liquid chamberand a source of liquid supply, and means adapted to operate in responseto the action of the diaphragm and to cause the transfer of liquid fromthe intermediate chamber into the impelling liquid chamber and from thesource of supply into the intermediate chamber.

HARRISON S. COE.

